Method and apparatus for installing offshore flow lines

ABSTRACT

Offshore flow lines are installed on an offshore structure in a body of water by pulling (and/or pushing) a flow line downwardly from water surface through a curved tubular member until one end of the flow line is available to water surface at a horizontally spaced-apart point from said structure. The flow line may be arranged in the curved tubular member when the offshore structure is built and the flow line pulled and/or pushed through it when the structure is located in a vertical position in a body of water.

United States Patent [72] Inventor Jamie F. Matthews, Jr.

Houston,Tex. [21] Appl. No, 859,055 [22] Filed Sept. 18. 1969 [4S]Patented July 27, 197] [73] Assignee Esso Production Research CompanyContinuation-impart of applimtion Ser. No. 797,749, Feb. 10, 1969, nowabandoned.

[54] METHOD AND APPARATUS FOR INSTALLING OFFSHORE FLOW LINES 37 Claims,10 Drawing-Figs.

[52] US. Cl....'. 166/.5, 1/72: [51] 1nt.Cl ..E21b43/0l, F161 1/00 [50]Field ofSearch 61/723, 72.4; 166/.5,.6;175/220, 227

[56] References Cited UNITED STATES PATENTS 2,345,816 4/1944 Hays175/227 X 2,453,038 11/1948 Rossmann 175/220 X 2,810,440 10/1957Kenneday et al. 166/.5 X 3,219,119 11/1965 Matthews 61/723 X 3,258,9287/1966 Broadway et al. 61/72.3 3,298,092 1/1967 Dozier et al. 61/72.3 X3,346,045 10/1967 Knapp et a1 166/.5 3,431,739 3/1969 Richardson et al..61/723 3,434,296 3/1969 Otteman et al. 61/723 3,438,213 4/1969 Broussardet al. 6l/72 3 Primary Examiner-Ian A. Calvert Attorneys-Timothy L.Burgess, Thomas B. McCulloch,

Melvin F. Fincke, John S. Schneider, Sylvester W. Brock, Jr. and Kurt S.Myers PATENTED JUL2 7 I97! SHEET 2 0F 4 ATTO PATENTED JUL27 ISII SHEET l0F 4 FIG. 8.

PULLING FORCE PUSHING FQRCEE r I INV/jN'I'UR.

JAMIE F. MATTHEWS, JR. BY

METHOD AND APPARATUS FOR INSTALLING OFFSHORE FLOW LINES CROSS-REFERENCETO RELATED APPLICATIONS This application is a continuation-impart ofSer. No. 797,749 entitled Method for Installing Offshore Flow Lines"filed Feb. 10, 1969, for Jamie F. Matthews, Jr., now abancloned.

I BACKGROUND OF THE INVENTION conduit.

2. Description of the Prior Art It is known to install a flow line on anoffshore structure by pulling a flow line upwardly from water bottomthrough a curved conduit. This is the so-called .I-tube method whichinvolves pulling the flow line from a barge by a wire line, cable, andthe like up through a .l-tube by force applied on the line from the deckof an offshore platform. This method is disadvantageous because the pullrequired is so great, if not properly controlled, it may cause at leastpartial failurc of the platform. Furthermore, the pull must besufficient to overcome the weight of the flow line running through thetube, the resistance of the pipe against being bent to conform to thecurvature of the .l-tube, and the friction between the outer surface ofthe flow line and the inner surface of the J-tube, of these threeforces, friction is the greatest. THe sum of these forces is so greatthat the J-tube method is currently limited to installation of flowlines of 10 inch maximum diameter. The present invention overcomes thesedisadvantages and, in fact, utilizes the weight of the pipe to assist inthe operation, reduces friction, and allows installation of flow linesof large diameter than heretofore possible with the J-tube Moreover,

the new method eliminates or reduces the use of divers since all or mostof the operations may be conducted from water surface.

The following U.S. patents were considered in connection with thisinvention: U.S. Pat. Nos. 3,258,928; U.S. Pat. No. 3,331,2l2;3,434,296;

BRIEF DESCRIPTION OF THE DRAWING The present invention will be furtherillustrated by reference to the drawing in which:

FIG. 1 is a view showing the initial steps of installing a flow line ona submerged structure;

FIG. 2 illustrates the flow line being pulled downwardly to a submergedstructure from water surfaces;

FIG. 3 is a showing of connecting flow line to a wellhead on thesubmerged structure;

FIG. 4 illustrates he invention as applied on a structure extendingabove water surface;

FIG. 5 is a modification of the invention in which a submerged conduitis employed on a structure extending above water surface and the flowline is pulled and/or pushed through the conduit;

FIG. 6 is an elevational view of an offshore structure with the deckremoved;

FIG.'7 is a plan view of the structure of FIG. 6;

FIG. 8 is an enlarged detail of the lower end of the riser of FIG. 7;

FIG. 9 illustrates another means for removing curvature from the flowline; and

FIG. 10 is a sectional view along line 10-10 of FIG. 9 i

SUMMARY OF THE INVENTION The present invention may be briefly describedand summarized as involving a method of installing a flow line on anoffshore structure, either submerged or extending above water level, byrunning a flow line downwardly through an openended curved tubularconduit on the offshore structure until both ends are accessible fromwater surface. This is accomplished by pulling and/or pushing the lowline downwardly from water surface through the curved conduit until theflow line is pulled and/or pushed to anacccssiblc location horizontallyspaced from the offshore structure. The flow line is preferably pulledthrough the tubular conduit by a cable or the like threaded through thetubular conduit.

DESCRIPTION OF THE PREFERRED MODE AND EMBODIMENTS WITH RESPECT TO THEDRAWING Referring now to the drawing and particularly to FIG. 1, numerall1 designates a body of water having a bottom 12 and surface 13 on whichis floating a work vessel 14 and a lay barge 15. The work vessel 14 isprovided with a hoisting mechanism 16 which may be a drilling rig, andthe lay barge 15 is provided with a rack 17 of flow line pipe anda'hoisting mechanism 18 which may be a suitable winch. Actually in FIG.1, the distance of the lay barge l5 and platform 21 from the work vessel14 is much greater than is shown. The relative distance between the twovessels should be such that the pull is more nearly in a horizontalposition than that shown.

Arranged on water bottom 12 and securely anchored thereto by members 19which may be cross braced with cross bracing 20 is submerged platform21. The members 19 extend into and are securely anchored in water bottom12 as shown.

As well 22 has been drilled to penetrate a productive subsurfaceformation which may contain oil and/or gas and extends to the platform21 and is provided with a wellhead 23 including a suitable valvemechanism.

Prior to installing the platform 21, it is equipped with a curvedtubular 24 which has a flared open end 25 and a flared open end 26 onthe platform 21. A cable, chain, wire line, or the like, 27 is threadedthrough the tubular conduit 24 and extends into and is connected withthe winch 18. The other ends of cable 27 extends to the work vessel 14and is connected to the lowerend of a fabricated flow line pipe 28 bymeans of a connector plug 28a, As the flow line is lowered throughvessel 14, it is it the same time pulled into and through the curvedpipe 24 by means of the winch 18.

As shown more clearly in FIG. 2, the tubular flow line 28 connected toline 27 has been pulled through tubular conduit 24 from the vessel 14 bysuitable force exerted by the winch 18 pulling on the line 27.

In FIG. 3, the flow line 28 has been pulled from the vessel 14 throughthe tubular conduit 24 by line 27 so that the end provided with plugconnector 28a, is raised from the surface of the water and is adjacentthe lay barge 15. At this time a clamping means 40 is applied to supportthe pipe 28 and the plug conductor 28a, removed from the end of thepipe.

It will also be seen in FIG. 3, that a wellhead connection 29 has beenlowered onto the end of flow line 28 by wire lines 30 connecting withthe work vessel 14 and the flared end 26 of tubular conduit 24; aconnection 31 being remotely controlled from the vessel 14 with thewellhead 23, connecting to the well pipe 23a, through conductor pipe23b.

Thus, it will be seen with the description taken with the drawing andwith reference to FIGS. 13 that a flow line may be installed andconnected to a well without resort to divers. Thereafter, lengths ofpipe may be added to the end 41 to extend the flow line to a suitableterminal for oil and/or gas and the like.

Referring to FIG. 4, a platform supported above the water surface 13 onmembers 51 suitably cross braced with cross bracing 52 has a drillingrig 53 including hoisting means 54 thereon located on a platform 50. Inthis particular instance, a plurality of wells 55 have been drilled fromthe platform 50 by moving the drilling rig 53. In this particularinstance, a flow line 56 connected by line 57 to the hoisting means 54has been pulled through a curved tubular conduit 58 having flared ends59 by means of the winch 18 connected by line 27 to the end 41 of flowline 56. The hoisting line 57 is used to connect successive lengths ofpipe during the pulling operation. In this particular embodiment, thework vessel 14 has been replaced by the platform 50.

Once the flow line 56 has been pulled through the tubular member 58, itthen may be connected to the wellheads 60 of the several wells 55drilled from platform 50 for production of oil through the flow line 56.

It is within the purview of the present invention to push as well aspull through the tubular conduit and this is best illustrated in FIG. towhich reference is now had. In this particular instance, platform 50,similar to that shown in FIG. 4, is supported by members 51. A submergedcurved tubular conduit 70 is arranged on the platform 50 below waterlevel 13 and above water bottom 12. Line 27 connects to a tubular flowline 28 by suitable plugged connection means 280. In this particularmode and embodiment, the flow line 28 is both pulled and pushed throughthe tubular member 70 and this is accomplished by pulling on the line 27and exerting downward force on the tubular flow line 28. This isachieved by attaching a connection member 73 to the flow line 28 and inturn connecting it by lines 74 running over sheaves 75 to a hoistingmechanism such as 54 shown in FIG. 4. By pulling on lines 74, a downwardpush or force is exerted on the flow line 28 at the same time tension isexerted by line 27 which causes a combined push and pull on the flowline 28 which is quite beneficial as will be explained further.

Thus, in accordance with the present invention, with reference to FIGS.1-4, inclusive, gravity which heretofore had to be overcome to lift theweight of the flow line now works to assist the operation. Moreimportantly, however, than the weight is the effect of the simultaneouspushing and pulling of the flow line, as shown in FIG. 5, in reducingthe friction in the tubular conduit 70 since a flow line being moved orrun in tubular conduit 70 or the like by pulling force alone tends tobind against the throat of the tubular conduit and severe friction isgenerated. The pushing force on the same flow line tends to relieve thispressure and friction is thereby reduced. Similarly, the pulling forcetends to reduce friction generated by the pushing force. THe reaction ofboth on the flow line results in friction resistance which has beenreduced and is much less than if either force were acting alone. Inaccordance with the present invention with a pushing force and withreduced friction, it is now possible to install flow lines of a largerdiameter than has been possible heretofore. This may be accomplishedwith substantially reduced danger on parting the pulling cable and withless danger of overstressing; if the pushing force supplied by gravityis insufficient it may be supplied as shown in FIG. 5.

The present invention allows the installation of connection means on theplatform end ofthc flow line before it is lowered into the water asshown in FIG. 3. Otherwise, for an underwater platform this wouldrequire pulling the flow line into place upwardly, and cutting thepulling head by a welding torch or other cutting means such as amechanical cutter.

Referring now to FIGS. 6 to 9 inclusive, in which another mode of thepresent invention is illustrated, numeral 80 illustrates an offshorestructure, provided with a curved conduit 81, arranged in a verticalposition in a body of water II. The curved conduit 81 has its lower end82 at least adjacent to the bottom of the body of water and its upperend 83 at least adjacent the upper end of the structure 80. Thestructure 80 is provided with legs 84 and crossmembers 85 which may besuitably braced as shown in FIGS. 6 and 7 by members 86 and 87. Theconduit 81 has a flow line 88 extending through it which is provided onits lower end with a pulling head 89 which is shown in more detail inFIG. 8. The pulling head 89 is connected to the flow line 88 by flange90 and blind flange 91 by bolts 92. A suitable cable may be connected tothe pulling head 89 by padeye 93 for pulling the flow line 88 throughthe conduit 81.

It will be noted in FIG. 6 that the conduit 81 has a first section,designated by the numeral 94, which has a curvature with a radius in onedirection, whereas the section 95 between the markers A and B has areverse curvature or radius. The purpose of the reverse curvature is toremove residual curvature or set from the flow line 88 as it is pulledthrough the conduit 81.

The removal of residual curvature or set offlow line 88 may beaccomplished by other means such as illustrated in FIGS. 8,9 and 10wherein the conduit 81 is provided adjacent its lower end with rollers97 in the area 95 between markers A and B. As shown in FIG. 10, therollers 97 extend into the interior of conduit 81 through slots 96 andare pivoted on axles 98 carried on yokes or plates 99. A roller 9711,located on the underside of conduit 81 may extend deeper into theconduit than the rollers 97. As the flow line 88 passes between thesethree rollers 97, 97a, and 97 it is forced into an opposite curvatureand thus will be straightened, removing the residual curve. The rollersin the area 95 function as a means for straightening the flow line as itpasses through the conduit 81.

Other rollers 100, which are identical to the rollers 97 may bepositioned along the other section of conduit 81 to contact the flowline 81 and reduce friction as the flow line is moved through theconduit. However, rollers 100 may be used wherever desired on theconduit 81. The location and number of rollers may vary with the size ofthe conduit 81, the flow line 88 and the radius of the conduit 81. Threerollers will usually be sufflcicnt but more or less may be used. AS ageneral rule the rollers may be placed wherever the flow line 88 tendsto contact the interior of conduit 81. Anywhere from one to 10 or morespaced-apart horizontally and vertically spaced-apart rollers may beused.

In the practice of the present invention, as illustrated in FIGS. 6 to9, flow line 88 is installed in the conduit 81 during land fabricationof the structure and may be pulled through the conduit 81 as has beendescribed. Once the structure is located vertically in body of water 11,as shown in FIG. 6, and difficulty is experienced in pulling the flowline 88 through the conduit 81, then the flanges and 91 may be unboltedand an underwater connection made to an extended flow line such as 56,shown in FIG. 4, either through use ofdivers or remotely with means wellknown in the art.

However, it has been found that the application of pushing force actingin conjunction with a pulling force in accordance with the presentinvention, as shown in and described with respect to FIG. 5, reduces thetotal force required to move the flow line downwardly through theconduit by almost 30 percent ofthat required in pulling the flow lineupwardly through the conduit It has also been found that if the flowline 88 is lubricated, the force required to pull and push it downwardlythrough the conduit 81 is reduced even further. For example, a length of1 A? pipe or tubing of the same size was then coated with a heavyfibrous grease such as used on heavy gears and/or on heavy dutyequipment was pulled and pushed through a conduit such as 81 with thetotal force reduced by 35 percent due to the reduction of friction. Itis, therefore, contemplated in the practice of the present inventionthat at least one of the contact surfaces between the internal wall ofthe conduit and the outer wall of the flow line may be coated with asuitable lubricant such as a heavy grease which may be used to reducefriction and to facilitate the pulling and pushing of a flow linethrough the conduit. The combined effect of applying pushing as well aspulling and use of lubricant has been to reduce the total force requiredby 55 percent. It will be noted that the percentages given before arenot directly additive. In short, in the practice of the presentinvention, it is contemplated that the interior of the conduit, or theexterior of the flow line, or both of them, may be coated with asuitable lubricant or grease to reduce total force required in pushingand/or pulling the flow line down through the conduit. When lubricationis used, rollers 97 may not be necessary. When rollers 97 are used, theonly lubrication which may be required is for the axles 98. Of courserollers and lubrication may be used but both may under some conditionsbe dispensed with. I

THe rollers provide two functions: (1 they facilitate movement throughthe conduit; and (2) they eliminate or remove residual curvature or set,both 'of which are quite advantageous and useful.

In accordance with the present invention, an underwater platform with acompleted well or wells may be connected to a production manifold with afloating drill rig in position over the top end of the curved tubularconduit which may be installed during fabrication on land. A work bargemay be substituted for a drilling vessel. in either instance a steelcable or chain is run through the tubular conduit to the drilling rig orhoisting means and the other end secured to the pipe laying barge inwhich sections of flow line pipe are racked. Thus. as illustrated,several sections of flow line pipe may be sequentially joined as shownon the drill floor of the rig as the flow line pipe is lowered into thecurved tubular member and the weight thereof and the tension appliedthereon causes the flow line pipe to move downwardly through the tubularmember and to be pulled to the barge 15. The set or curvature taken bythe flow line in passing through the curved tubular member is removed byreverse curvature as it leaves the curved tubular member.

Thus, in accordance with the present invention, flow lines are rundownwardly rather than upwardly through a tubular member by pulling andpushing on the ends thereof which results in improved operations as hasbeen brought out hereinbefore which results in numerous advantages.Thus, the present invention is quite important and useful and allows theobtaining of new and improved results not obvious from the prior art.The present invention is, therefore. quite advantageous and useful andallows the obtaining of economic and safety advantages not possibleheretofore.

The nature and objects of the present invention having been completelydescribed and illustrated and the best mode contemplated set forth, whatI wish to claim as new and useful and secure by Letters Patent is:

1. A method for installing a flow line having first and second ends onan offshore structure in a body of water wherein said structure isprovided with an open'ended curved tubular conduit having a first end atleast adjacent water bottom and a second end extending upwardly on saidstructure which comprises:

positioning a flexible member through said tubular conduit with thefirst end of said flexible member extending from the first end of saidconduit to water surface at a horizontally spaced apart point from saidstructure and the second end of the flexible member extending from thesecond end ofsaid conduit;

attaching the first end of said flow line to the second end of saidflexible member; and

then pulling said flexible member and the flow line downwardly throughsaid conduit until the first end of said flow line extends from thefirst end of said conduit to said point horizontally spaced apart fromsaid structure.

2. A method in accordance with claim 1 in which the offshore structureis submerged.

3. A method in accordance with claim 1 in which the offshore structureextends at least to water surface.

4. A method in accordance with claim 1 in which lengths of pipe areadded to the first end of said flow line at least adjacent water surfaceto increase the length thereof.

5. A method in accordance with claim 1, in which the flexible member isa cable.

6. A method in accordance with claim 1 in which the flexible member is achain.

7. A method in accordance with claim 1 in which the flexible member andthe flow-line are on a floating vesseland the structure and tubularconduit are submerged.

8. A method in accordance with claim 1 in which the flexible memberandthe flow line are on a fixed offshore structure extending at least towater surface and the tubular conduit also extends at least to watersurface.

9. A method in accordance with claim I in which the offshore structureis provided with said curved tubular conduit before the offshorestructure is placed in said body of water.

10. A method in accordance with claim 1 in which the point adjacentwater surface is a floating vessel horizontally spaced from saidstructure.

11. A method in accordance with claim 1 in which the outer wall of theflow line is lubricated.

12. A method in accordance with claim 1 in which the flow line is pushedat the same time it is being pulled by exertion of force on the secondend.

13. A method in accordance with claim 1 in which:

a. lengths of pipe are added to the first end of said flow line at leastadjacent water surface;

b. the flexible member is a cable;

0. the flexible member is positioned by running it downwardly throughsaid conduit;

d. the offshore structure is provided with said curved tubular conduitprior to placement of the structure in said body of water; and

e. the flow line is pushed at the same time it is being pulled byexertion of force on the second end.

14. A method in accordance with claim 1 in which the flexible member ispositioned in said conduit by pulling same from said structure to saidlocation horizontally spaced apart from said structure.

15. A method in accordance with claim 14 in which the location is on afloating vessel.

16. A method for installing a flow line having first and second ends onan offshore structure in a body of water wherein said structure isprovided with an open-ended curve tubular conduit having a and end atleast adjacent water bottom and a second end extending vertically onsaid structure which comprises:

running the first end of a flow line from water surface into the secondend of said curved conduit and out the first end of said conduit andthen to a point at least adjacent water surface horizontally spaced fromsaid structure until the second end of said flow line is accessible fromsaid structure and the first end is accessible from water surface.

17. A method in accordance with claim 16 in which the flow line ispulled and pushed through said curved conduit.

18. A method in accordance with claim 17 in which a lubricant is appliedto at least one of the contact surfaces between the inner wall of theconduit and the outer wall of the flow line.

19. A method in accordance it claim 17 in which the outer wall of theflow line is lubricated.

20. A method in accordance with claim 16 in which the flow line ispushed through said curved conduit.

21. A method in accordance with claim 16 in which the second end of thetubular conduit extends at least to water surface.

22. Amethod in accordance with claim 16 in which the tubular conduit issubmerged.

23. A method in accordance with claim 16 in which a lubricant is appliedto at least one he contact surfaces between the inner wall of theconduit and outer wall of the flow line.

24. A method in accordance with claim 16 in which the flow lincis runinto said curved conduit by pulling.

25. A method for installing a flow line having first and second ends ona structure located vertically offshore in a body of water wherein saidstructure is provided with an openended curved tubular conduit having afirst end located at least adjacent water bottom and a second endextending vertically on said structure, said conduit having a flow linearranged therein with a first end adjacent the first end of the conduitand the second end extending from the second end of the conduit whichcomprises:

moving said flow line through said curved conduit and out the first endofsaid conduit such that said first end of said flow line is accessiblefrom water surface spaced horizontally from said structure and thesecond end is accessible from said structure.

26. A method in accordance with claim 25 in which the flow line ispulled through said curved conduit.

27. A method in accordance with claim 25 in which the line is pulled andpushed through said curved conduit.

28. A method in accordance with claim 27 in which a lubricant is appliedto at least one of the contact surfaces between the inner wall of theconduit and the outer wall of the flow line.

29. A method in accordance with claim 25 in which the outer wall oftheflow line is lubricated.

30. A method in accordance with claim 25 in which the residual curvatureor set of the flow line is removed when said flow line is run throughsaid conduit.

3]. A method in accordance with claim 30 in which the residual curvatureor set is removed by running the flow line through a portion of theconduit having a radius of curvature in reverse to that ofthe mainportion the conduit.

32. A method in accordance with claim 25 in which the end of the flowline adjacent water bottom is connected to a pipe line.

33. A method for installing pipe in a body of water using pipe contactmeans including a member having structure adapted to contact pipe onsubstantially opposite sides thereof capable of changing the directionof movement of said pipe from a generally vertical to a generallyhorizontal direction which comprises attaching one end of a flexiblemember extending through said pip contact means to said pipe and thenmoving said flexible member and said pipe downwardly through said pipecontact means until said pipe extends through said pipe contact means toa point horizontally spaced a substantial distance from said pipecontact means.

34. A method in accordance with claim 33 in which said pipe contactmeans and at the same time said pipe is pulled through said pipe contactmeans.

35. A method in accordance with claim 3 in which residual curvature orset is removed from said pipe as the pipe traverses said pipe contactmeans.

36. Apparatus for installing pipe in a body of water which comprises:

pipe contact means including a member having structure adapted tocontact pipe on substantially opposite sides thereof capable of changingthe direction of movement of a pipe from a generally vertical to agenerally horizontal direction when said pipe is moved downwardlythrough said pipe contact means means for moving pipe downwardly throughsaid pipe contact means; and

means arranged adjacent said pipe contact means for removing residualcurvature or set from the pipe as said pipe travers said pipe contactmeans.

37. Apparatus as recited in claim 36 including means within said pipecontact means for facilitating the movement of pipe through said pipecontact means.

1. A method for installing a flow line having first and second ends on an offshore structure in a body of water wherein said structure is provided with an open-ended curved tubular conduit having a first end at least adjacent water bottom and a second end extending upwardly on said structure which comprises: positioning a flexible member through said tubular conduit with the first end of said flexible member extending from the first end of said conduit to water surface at a horizontally spaced apart point from said structure and the second end of the flexible member extending from the second end of said conduit; attaching the first end of said flow line to the second end of said flexible member; and then pulling said flexible member and the flow line downwardly through said conduit until the first end of said flow line extends from the first end of said conduit to said point horizontally spaced apart from said structure.
 2. A method in accordance with claim 1 in which the offshore structure is submerged.
 3. A method in accordance with claim 1 in which the offshore structure extends at least to water surface.
 4. A method in accordance with claim 1 in which lengths of pipe are added to the first end of said flow line at least adjacent water surface to increase the length thereof.
 5. A method in accordance with claim 1, in which the flexible member is a cable.
 6. A method in accordance with claim 1 in which the flexible member is a chain.
 7. A method in accordance with claim 1 in which the flexible member and the flow line are on a floating vessel and the structure and tubular conduit are submerged.
 8. A method in accordance with claim 1 in which the flexible member and the flow line are on a fixed offshore structure extending at least to water surface and the tubular conduit also extends at least to water surface.
 9. A method in accordance with claim 1 in which the offshore structure is provided with said curved tubular conduit before the offshore structure is placed in said body of water.
 10. A method in accordance with claim 1 in which the point adjacent water surface is a floating vessel horizontally spaced from said structure.
 11. A method in accordance with claim 1 in which the outer wall of the flow line is lubricated.
 12. A method in accordance with claim 1 in which the flow line is pushed at the same time it is being pulled by exertion of force on the second end.
 13. A method in accordance with claim 1 in which: a. lengths of pipe are added to the first end of said flow line at least adjacent water surface; b. the flexible member is a cable; c. the flexible member is positioned by running it downwardly through said conduit; d. the offshore structure is provided with said curved tubular conduit prior to placement of the structure in said body of water; and e. the flow line is pushed at the same time it is being pulled by exertion of force on the second end.
 14. A method in accordance with claim 1 in which the flexible member is positioned in said conduit by pulling same from said structure to said location horizontally spaced apart from said structure.
 15. A method in accordance with claim 14 in which the location is on a floating vessel.
 16. A method for installing a flow line having first and second ends on an offshore structure in a body of water wherein said structure is provided with an open-ended curve tubular conduit having a and end at least adjacent water bottom and a second end extending vertically on said structure which comprises: running the first end of a flow line from water surface into the second end of said curved conduit and out the first end of said conduit and then to a point at least adjacent water surface horizontally spaced from said structure until the second end of said flow line is accessible from said structure and the first end is accessible from water surface.
 17. A method in accordance with claim 16 in which the flow line is pulled and pushed through said curved conduit.
 18. A method in accordance with claim 17 in which a lubricant is applied to at least one of the contact surfaces between the inner wall of the conduit and the outer wall of the flow line.
 19. A method in accordance it claim 17 in which the outer wall of the flow line is lubricated.
 20. A method in accordance with claim 16 in which the flow line is pushed through said curved conduit.
 21. A method in accordance with claim 16 in which the second end of the tubular conduit extends at least to water surface.
 22. A method in accordance with claim 16 in which the tubular conduit is submerged.
 23. A method in accordance with claim 16 in which a lubricant is applied to at least one he contact surfaces between the inner wall of the conduit and outer wall of the flow line.
 24. A method in accordance with claim 16 in which the flow line is run into said curved conduit by pulling.
 25. A method for installing a flow line having first and second ends on a structure located vertically offshore in a body of water wherein said structure is provided with an open-ended curved tubular conduit having a first end located at least adjacent water bottom and a second end extending vertically on said structure, said conduit having a flow line arranged therein with a first end adjacent the first end of the conduit and the second end extending from the second end of the conduit which comprises: moving said flow line through said curved conduit and out the first end of said conduit such that said first end of said flow line is accessible from water surface spaced horizontally from said structure and the second end is accessible from said structure.
 26. A method in accordance with claim 25 in which the flow line is pulled through said curved conduit.
 27. A method in accordance with claim 25 in which the line is pulled and pushed through said curved conduit.
 28. A method in accordance with claim 27 in which a lubricant is applied to at least one of the contact surfaces between the inner wall of the conduit and the outer wall of the flow line.
 29. A method in accordance with claim 25 in which the outer wall of the flow line is lubricated.
 30. A method in accordance with claim 25 in which the residual curvature or set of the flow line is removed when said flow line is run through said conduit.
 31. A method in accordance with claim 30 in which the residual curvature or set is removed by running the flow line through a portion of the conduit having a radius of curvature in reverse to that of the main portion the conduit.
 32. A method in accordance with claim 25 in which the end of the flow line adjacent water bottom is connected to a pipe line.
 33. A method for installing pipe in a body of water using pipe contact means including a member having structure adapted to contact pipe on substantially opposite sides thereof capable of changing the direction of movement of said pipe from a generally vertical to a generally horizontal direction which comprises attaching one end of a flexible member extending through said pip contact means to said pipe and then moving said flexible member and said pipe downwardly through said pipe contact means until said pipe extends through said pipe contact means to a point horizontally spaced a substantial distance from said pipe contact means.
 34. A method in accordance with claim 33 in which said pipe contact means and at the same time said pipe is pulled through said pipe contact means.
 35. A method in accordance with claim 3 in which residual curvature or set is removed from said pipe as the pipe traverses said pipe contact means.
 36. Apparatus for installing pipe in a body of water which comprises: pipe contact means including a member having structure adapted to contact pipe on substantially opposite sides thereof capable of changing the direcTion of movement of a pipe from a generally vertical to a generally horizontal direction when said pipe is moved downwardly through said pipe contact means means for moving pipe downwardly through said pipe contact means; and means arranged adjacent said pipe contact means for removing residual curvature or set from the pipe as said pipe traverses said pipe contact means.
 37. Apparatus as recited in claim 36 including means within said pipe contact means for facilitating the movement of pipe through said pipe contact means. 